Matthew Bate's Animations

Radiation hydrodynamical simulations of star formation in a 500 solar-mass molecular cloud with different metallicities, ranging from 1/100 to 3 times solar metallicity. For the first time, these calculations treat separate gas and dust temperatures and include a model for the diffuse interstellar medium and a simple chemical model. It is found that close binary systems are more frequent at lower metallicity, due to enhanced cooling and fragmentation on small spatial scales. More information.

We present results from the first population synthesis study of protostellar discs. We analyse the evolution and properties of a large sample of protostellar discs formed in a radiation hydrodynamical simulation of star cluster formation.
Due to the chaotic nature of the star formation process, we find an enormous diversity of young protostellar discs, including misaligned discs, and discs whose orientations vary with time. Star-disc interactions truncate discs and produce multiple systems.
Discs may be destroyed in dynamical encounters and/or through ram-pressure stripping, but reform by later gas accretion.
We quantify the distributions of disc mass and radii for protostellar ages up to ≈ 105 yrs.
More information.

We study the evolution of dust and gas during the collapse of rotating molecular cloud cores.
We show that the dynamics of the dust depends on its size. Dust particles with sizes <10 microns are well-coupled to the gas during the collapse and there is little variation of the dust-to-gas ratio. However, larger dust grains (e.g. 100 micron or 1 mm) have trajectories that are very different from the gas, leading to mid-plane settling and/or oscillations if the dust through the mid-plane.
This may produce variations in the dust-to-gas ratio and very different distributions of large and small dust grains at the very earliest stages of star formation, if large grains are present in pre-stellar cores. More information.

We investigate the evolution of a dusty protoplanetary disc with two different dust species (1 mm and 50 cm dust grains), under the presence of the toroidal vortex instability. We show how toroidal vortices, triggered by the interaction of mm grains with the gas, stop the radial migration of metre-sized dust, potentially offering a natural and efficient solution to the dust migration problem. More information.

We report a new hydrodynamical instability in protoplanetary discs that may arise due to variations in the dust-to-gas ratio and may lead to concentration of dust grains within a disc. More information.

Radiation magnetohydrodynamical simulations of the collapse of 1 solar-mass molecular cloud cores that follow the formation of the first core or pre-stellar disc, a slow magnetically-driven outflow from the first core, the second collapse and the formation of the stellar core, and the launching of a fast outflow from the vicinity of the stellar core. More information.

Radiation hydrodynamical simulations of the collapse of 1 solar-mass molecular cloud cores that follow the formation of the first core or pre-stellar disc and its evolution before and after the formation of the stellar core within it. More information.

AVI (13MB) AVI (160MB) Quicktime (22MB)
A binary system forms first from an initial m=2 density perturbation
in the cloud. Subsequently, one of the protostellar discs fragments
to give a third object. The result is a stable triple system
surrounded by a circumtriple disc.

Many of the theoretical calculations I conduct during
my research into star and planet formation result in
animations. I will endevour to place as many of these
computer simulations as I can on this page. New animations
will be added at the top of the page with the dates that
they were added.

Copyright: Unless otherwise
stated, all of the material on this site
is the property of Matthew Bate. Any of my pictures and
animations may be used freely for non-profit purposes
(such as during scientific talks) as long as appropriate
credit is given wherever they appear. Permission must
be obtained from me before using them for any other
purpose (e.g. pictures for publication in books).